Raise Boring A

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Raise boring equipment2 PAlSL 8CPlNG LQUlPMLNTFlexible spacingOptimum button designExtendable reaming headsAll components are bolted togetherSegmented reaming heads Special gauge saddle system PAlSL 8CPlNG LQUlPMLNT 3Segmented reaming heads Reaming heads for any raise boring projectThe Sandvik Raise Boring System includes a wide range of reaming heads in a number of types, sizes and confgurations for boring holes from 0.6 to 6 meters in diameter. Designed for optimum performance in any type of project, the equipment is built according to certain fundamental principles. All basic components are bolted to each other, which enables fast and easy mounting, assembly and servicing. Since the stem is bolted to the base-head, different sizes of stem can be ftted to suit different sizes of pilot hole. The saddles, too, are bolted to the head. They are therefore easy to re-position, which gives maximum fexibility. The Sandvik system is based on standard components, which contributes greatly to its fexibility and high availability. All heads have a fat cutting profle which rotates smoothly and with optimum thrust utilisation. Sandvik reaming heads are easy to adapt to different rock conditions by re-arranging the cutters. The effect is to change the spacing between the rows of cemented-carbide but-tons that break the rock. To enable row spacing to be varied, only two types of cutter are needed on any one reaming head. Placing one or the other type of cutter in different positions on the head gives either wide or narrow button-row spacing. The unique design of Sandvik cemented-carbide buttons ensures long service life and the highest possible rate of penetration. A special gauge saddle system has been developed with the option to reduce the reamer diameter in two steps simply by changing to diffrent types of saddle. This option can be used in any project with heavy gauge wear and it makes it easier to reach the rock face if the reamer is lowered for any service. Larger diameter Sandvik reaming heads are available in segmented versions, which enable transport dimensions and weight to be reduced for projects in which there are size or weight restrictions. We also offer a wide range of extendable reaming heads, which can be built to different diameters by fxing segments of different types and sizes to the base-head.^ PAlSL 8CPlNG LQUlPMLNTConvential raise boringDown boring Blind hole boringPilot hole boringHorisontal boring PAlSL 8CPlNG LQUlPMLNT 5Pilot drillingConventional raise boring begins with the drilling of a pilot hole. It is drilled using a roller bit with sealed bearings, together with hollow drill pipes 1.5 m in length with an international standard thread for hightorque applications. The cuttings are removed from the pilot hole with the aid of water fushing. Introduced through the center of the drill string, the water fows out of the drill bit and up through the annulus between the drill pipes and the hole wall. If required, the pilot drilling can be controlled by using a directional drilling system.Raise boringWhen the pilot hole breaks through into the lower level, the roller bit is removed and replaced with a reaming head. The reamer is rotated and pulled back toward the drilling unit. The cuttings fall by gravity into the chamber at the bottom of the hole, where they are mucked out using a LHD-type loader. Raises up to 6 m in diameter and up to 1000 m in length are not uncommon. The raise-boring method is used to produce ventilation shafts, ore passes, manways, penstocks etc.Blind boringWhen a raise is required but there is no access to the upper level, it has to be bored blind from below, usually without a pre-drilled pilot hole. A special type of head is required for blind boring. It drills the pilot hole and reams out the raise at the same time. The head is rotated and pushed upward. The cuttings fall out of the hole by gravity. Normal blind raise diameters are from 0.6 to 1.8 m. Since the drill string is under compression during blind boring, special large-diameter stabilizers are needed to support the drill string. The blind-boring method is used to produce so-called slot raises, ore passes and manways.Horizontal boringHorizontal boring is an excellent method in urban construction projects where drilling and blasting is restricted or forbidden and tunnel boring machines (TBMs) are too bulky. First, a horizontal pilot hole is drilled, with the aid of a directional drilling system if necessary. When the pilot bit breaks through, it is removed and replaced with a reaming head. Because the hole is horizontal, the reamer must be equipped with a special cuttings removal system. Typical diameters for horizontal reaming are from 0.6 to 4.5 m. The method is used to drill tunnels for cables, escape routes, sewage etc without disturbing the environment unduly. Horizontal boring requires good rock stability.Down boring with a pre-drilled pilot holeIn mines, large fll-holes between 0.6 and 1.8 m in diameter can be bored into stopes using reaming equipment, provided that a pilot hole can be pre-drilled into the stope. The pilot bit and drill string are then removed and a reamer ftted. The reamer is pushed and rotated downward, guided by a nosepiece that follows the pilot hole. The cuttings fall by gravity down through the pilot hole. Since the drill string is under compression during down boring, special large-diameter stabilizers are needed to support the drill string.Raise boring methods6 PAlSL 8CPlNG LQUlPMLNTSegmented reaming headIntegral reaming headExtendable reaming heads PAlSL 8CPlNG LQUlPMLNT 7Sandvik RS510 integral reaming headsA Sandvik RS510 integral reaming head is the frst choice for any raise boring project in which there are no size or weight restrictions. The integral head is very strong and rigid. The stem, saddles and cutters are bolted to the head and easy to service. All Sandvik integral reaming heads have a fat cutting profle for smooth rotation and low torque demands. There are various stem-ft and saddle options. Stem sizes from 228 to 381 mm (9-15) can be used.Sandvik RS520 segmented reaming heads Sandvik RS520 segmented reaming heads should be chosen for projects in which there are restrictions on transport weights or dimensions. The segmented design comprises a base-head and two removable segments. This enables the reamer to be transported to the collaring site via small cages and narrow drifts. The segments are then fxed to the base-head using standard tools. Sandvik segmented reaming heads, too, have a flat cutting profile for optimum performance. All components such as the stem, segments, saddles and cutters are attached by bolts. This makes them very versatile and enables quick and easy servicing. There are various stem-ft and saddle options. Stem sizes from 228 mm to 349 mm (9-13 ) can be used. Sandvik RS530 extendable reaming heads Sandvik RS530 extendable reaming heads consist of a base-head to which four or six segments can be ftted. That means the reaming head can be built to different diameters. Sandvik extendable reaming heads are therefore a good option for any project in which there are both size and/or weight restrictions and high demands for hole-size fexibility. Segmentation allows the reamer to be transported to the collaring site via small cages and narrow drifts. The segments are then fxed to the base-head using standard tools. Sandvik extendable reaming heads, too, have a fat cutting profle for optimum performance. All components such as the stem, segments, saddles and cutters are attached by bolts. This makes them very versatile and enables quick and easy servicing. Different centre bores (stem-fts) and saddle options are available. Stem sizes from 280 to 381mm (11-15) can be used. The RS530 system permits raises of several different diameters to be bored with one and the same reaming head, thus reducing capital cost and keeping inventories to a minimum.Our types of reaming heads8 PAlSL 8CPlNG LQUlPMLNTHorizontal reaming head with scraper bladesBlind boring head CutterSaddlesStemPilot bits PAlSL 8CPlNG LQUlPMLNT 9In addition to the wide range of standard reaming heads for conventional raise boring, Sandvik offers to tailor-make reaming systems for any application that requires special design features. Examples include: Blind-hole boring systems with water-flushing, different drill-pipe to reamer connections and different stems to fit different sizes of pilot hole Down-boring systems with V-shaped reamers for improved cuttings removal while following a pre-drilled pilot hole, as well as different drill-pipe to reamer connections and removable wear-pad stem sleeves Horizontal-boring systems with scrapers and water fushing for effcient cuttings removal Underwater-reaming systems with pressure-compensated cutters and specially segmented components that are easy to handleAs with all Sandvik reaming heads, our tailored systems are designed and built in accord-ance with proven principles using: Bolted components for fast, easy handling and quick servicing Standard components for high availability, good fexibility and low inventories Flat cutting profles for smooth rotation, optimum thrust utilization and performancePlease consult your nearest Sandvik raise-boring specialist if your project needs a tailored solution.Components and Spare partsKey components for all standard reaming heads are always available from stock. Examples of standard-stock items include: Cutter types CMR 41 and CMR 52, which cover most applications Saddles for different positions and different types of reaming head Stems for different pilot-hole diameters with threads to ft any size of drill pipe Sealed bearing pilot bits featuring special designed gauge buttons in DP cemented carbide for high gauge wear resistance and high performanceFor more detailed information about components, spare parts and ordering numbers, please s

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